if you have lupus anticogulant it isn't a matter of finding the right INR target. The problem is it isnt reliable and flucuates and even though the INR might come back as 15, you may be at a theraputic level. A hematologist can order different tests to find your theraputic level. My doctor checks by doing a protein assay or something ( i should know this by now.) Im 31 and have been dealing with this for 5 years after a dvt in my leg and finding out i have lupus antcoagulant and factor leiden v.